Experiments have been a staple in the realm of science. Both thought experiments and actual physical experiments have been conducted throughout history and even in the present to understand our world with a better perspective. Experiments in motion physics are fairly easy to understand in simpler language, but when it comes to quantum physics, laws of physics that apply to us and other objects just seem to break. A hypothetical situation that has been quite popular with physicists is Schrödinger’s Cat Paradox.
The Experiment
As mentioned earlier it was not a real experiment but a hypothetical one, which to this day is considered one of the most influential thought experiments in quantum physics. Though Schrödinger dismissed and disagreed with the principle his experiment is based on, scientists still hold his theory as true and one of the best examples of the Copenhagen Interpretation. It was conducted by an Austrian physicist, Erwin Schrödinger in the year 1935 during a discussion Schrödinger had with Albert Einstein to illustrate what the Copenhagen Interpretation would actually be like in real life and to illustrate the problems with Niels Bohr theory.
- The Copenhagen Interpretation: Perhaps the one incident that led to one of the most essential series debates in the history of science. In Belgium, a group of brilliant scientists was joining a conference in 1927 among them were Albert Einstein and Niels Bohr. During this, Bohr presented his theory to Einstein stating that each and every particle in the universe exist in multiple states at once, and upon being observed the particle will have a definitive state. Of course, Einstein completely disagreed with it calling it superstition. Though the two never agreed they were good friends. However, Copenhagen Interpretation became the standard basis of quantum physics.
Albert Einstein and Niels Bohr at Paul Ehrenfest’s house.
- The Schrödinger’s Cat Paradox: In this imaginary experiment, Schrödinger theorized that a cat is to be placed in a box that is opaque along with a tiny radioactive matter, a Geiger counter (a device to measures ionizing radiation), and some sort of poison. As it is established that radioactive particles do decay and when it does it would trigger the Geiger counter. In addition to triggering the instrument, it would also cause the poison to be released, killing the cat. The box will be opened after one hour which will be enough time for the radioactive decay to occur and releasing the poison instantly. So, basically, the cat would either live or die right? Well, here’s the interesting part and the paradox. If we apply The Copenhagen Interpretation here, the cat is not just dead or alive as a probability but it exists in this dual state of being both dead and alive at the same time and it is only when the observer will open the box to check on the cat it will start to exist in only one state. This was one of the craziest ideas that has ever been presented and Schrödinger himself said it is not possible. Einstein even congratulated him, saying that his experiment just proves it cannot be possible. Though an imaginary experiment, it became such a mind-bending paradox that Erin Schrödinger himself gave up on Quantum physics and starting studying biology. However, scientists hold this as the best example of the Copenhagen Interpretation because of something known as Superposition.
Erwin Schrödinger lighting a pipe.
- Superposition: This quantum phenomenon is due to the duality of each matter being a wave and well, a particle. Being a particle is easy to understand that it occupies some amount of space and has physical properties. When it comes to the wave nature, it can only happen when a particle occupies multiple positions at the same time. The reason that is given behind why we cannot see the wave properties of each and every particle is because of the momentum of that object or person, as the momentum increases the wavelength decreases. Additionally, the wave nature of solid objects is minuscule, so small that the wavelength of a moving planet will be about the size of an atom, which obviously cannot be observed. Although it may sound philosophical and unreal, physicists are not just making these properties as it was strongly evident in the Double-Slit experiment.
- Double-Slit Experiment: Another famous experiment conducted regarding the nature of matter. Though first it was conducted in 1801 by Thomas Young using light, the influential addition to this experiment happened in 1927 by Clinton Davisson and Lester Germer when they used electrons to conduct the same experiment. It was seen that electrons going from two narrow slits exhibit the nature of particles which they are, as each electron was being detected at a specific point. However, the repetition of the shooting electrons towards these slits showed that they were following a set pattern, a wave pattern, meaning there were spots where electrons were densely present while other spots were empty on the screen, just like the crest and the trough of a wave. They did the experiment by blocking one of the slits and the second strip of electron simply didn’t exist. Electrons didn’t simply choose to go left or right, electrons were going both in the left and right direction at the same time resulting in the wave pattern. This further cements that Schrödinger’s cat experiment was in fact true.
A representation of the Double Slit Experiment.
Even though Schrödinger himself disagreed, in modern times it has been proven that his thought experiment was true and not just a paradox. All I can say is, I’m glad he didn’t actually conduct the experiment with an actual cat.
